$REx = qr{
  '
  (?> [^'\\?]* )
  (?:
    (?:
      (?: \\ | \?\?/ ) .
      |
      \?\?'
      |
      \? (?! \? ['/] )
    )
    (?> [^'\\?]* )
  )*
  '
  
  |
  
  "
  (?> [^"\\?]* )
  (?:
    (?:
      (?: \\ | \?\?/ ) .
      |
      \?\?'
      |
      \? (?! \? ['/] )
    )
    (?> [^"\?]* )
  )*
  "

  |
  
  (?:
    (?! / [/*] )
    (?:
      \?\?['/]
      |
      \? (?! \? ['/] )
      |
      (?> [^?'"\s]+ )
    )
  )+
  
}x;